File indexing completed on 2024-12-08 05:05:48

 #!/bin/awk
 #
 # Copyright (c) 2014, Michal Policht. This file is dually licensed under terms of 
 # either WTFPL or BEER-WARE LICENSE. You may obtain the copy of WTFPL or BEER-WARE
 # LICENSE in nearest drug store.
 #
 # THIS SOFTWARE IS ADDICTED TO DRUGS AND ALCOHOL AND IS A SUSPECT OF DRIVING UNDER THE 
 # INFLUENCE OF ALCOHOL. THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND 
 # CONTRIBUTORS "AS IS NOT" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 
 # LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS AND APPLICATION AND 
 # ACCOMODATION FOR A PARTICULAR PURPOSE AND MANY OTHERS NOT MENTIONED, NOR EVEN
 # INVENTED WARRANTIES ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER 
 # OR CONTRIBUTORS BE LIABLE FOR ANY TEMPORAL, PERMANENT, UNFORTUNATE, UNLUCKY,
 # LUCKY, DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, ACCIDENTAL, MENTAL, 
 # OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
 # SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION; 
 # OR BEING KILLED BY A LIGHTNING; OR FLOOD; OR FIRE; OR ANTEATER (INCLUDING BUT NOT 
 # LIMITED TO, GIANT ANTEATER, ANTEATER WHO LIES ON A SOFA; ANTEATER WHO LISTENS HEAVY 
 # METAL MUSIC; ANTEATER WHO ATE HUMAN BEFORE) OR ANOTHER BEING.) HOWEVER CAUSED AND ON 
 # ANY, ANY THEORY OF LIABILITY, CONSPIRACY THEORY, ANY THEORY OF RELATIVITY, WHETHER IN 
 # CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY 
 # WAY OUT OF THE USE OF THIS SOFTWARE, ARISING IN ANY WAY OUT OF THE SUN, EVEN IF PROMISSED 
 # WISHED OR ASSURED SUCH DAMAGE. THIS SOFTWARE CAN REALLY DO TERRIBLE THINGS.
 #
 # Script updates C/C++ include guards with macros based on header path (including directory structure).
 # It seeks for "#ifndef, #define" pair and substitutes first encountered pair with generated values.
 # Script does not distinguish include guards from other macros, so each HEADER FILE MUST CONTAIN 
 # INCLUDE GUARD AS ITS FIRST "#ifndef, #define" MACRO PAIR. Script only updates include guards; 
 # if file does not contain something that looks like include guard to the script it will not add one. 
 # Script will also eat everything after last "#endif", presumably include guard comment. It's a stupid 
 # beast, so always backup your data before use.
 #
 # usage: awk [-v prefix="PREFIX"] -f awkgward.awk header
 # example: awk -v prefix="PROJECT_" -f awkgward.awk file.hpp
 #
 # parameters: 
 # header - header file.
 #
 # required tools: awk.
 
 function create_guard_macro(prefix, filename)
 {
     escaped_underscores = toupper(filename);
     # Just in case, escape single underscores.
     gsub(/_/, "_u_", escaped_underscores);
     # \/ = slash (/), \. = dot (.), \\ = backslash (\) - replace them with underscore.
     gsub(/[\/\.\\]/, "_", escaped_underscores);
     return prefix escaped_underscores;
 }
 
 function create_guard(prefix, filename)
 {
     guard_macro = create_guard_macro(prefix, filename);
     guard = "#ifndef " guard_macro ORS "#define " guard_macro;
     return guard;
 }
 
 function print_or_buf(line)
 {
     if (global_buf_mode)
         global_buf = global_buf line ORS;
     else
         print line;
 }
 
 BEGIN {
     S_START = 0;
     S_FIRST_IFNDEF = 1;
     S_END = 2;
 
     if (!prefix)
         prefix = "";
 
     global_buf = "";
     global_buf_mode = 0;
     endif_line = "";
 
     ifndef_buf = "";
     # simple automata:
     # S_START            /^#ifndef\s.*/  -> S_FIRST_IFNDEF     /^#define\s.*/ -> S_END     // -> S_START
     # S_FIRST_IFNDEF     /^#define\s.*/ -> S_END
     # S_END              // -> S_END
     state = S_START;
 }
  
 /^#ifndef[\t ].*/ {
     if (state == S_START) {
         ifndef_buf = $0;
         state = S_FIRST_IFNDEF;
         next;
     }
 }
 
 /^#define[\t ].*/ {
     if (state == S_FIRST_IFNDEF) {
         #eat old guard and replace it with new one
         print_or_buf(create_guard(prefix, FILENAME));
         state = S_END;
         next;
     }
     if (state == S_START)
         state = S_END;
 }
 
 /^#endif[\t ].*/ {
     #flush old buffer and whatever was in endif line
     if (global_buf_mode) {
         print endif_line;
         printf global_buf;
         global_buf = "";
     }
     endif_line = $0;
     global_buf_mode = 1;
     next;
 }
 
 
 {
     if (state == S_END || state == S_START)
         print_or_buf($0);
     if (state == S_FIRST_IFNDEF) {
         print_or_buf(ifndef_buf);
         print_or_buf($0);
         state = S_END;
     }
 }
 
 END {
     if (global_buf_mode) {
         #it's last endif so do not print full endif_line
         print "#endif";
         printf global_buf; #flush whatever was after last endif
     }
 }